Semiconductor chip chemical grinding fluid supply method

Abstract

The invention discloses a semiconductor chip chemical grinding fluid supply method, and aims to improve the stability and accuracy of grinding fluid preparation and supply. Comprising the following steps: respectively storing grinding fluid components including a grinding particle suspension, a chemical additive and the like; performing multi-stage filtration on the grinding particle suspension through a precision filtration system to form a filtration suspension with preset particle distribution; accurately mixing the filtered suspension, the chemical additive solution and the diluent according to a preset proportion by adopting a dynamic mixing device to form a chemical grinding fluid; and the grinding liquid is supplied to the semiconductor chip grinding equipment through the dynamic fluid control system, so that the stability of the grinding process is ensured. The method solves the problems of purity, uniformity and supply stability of the grinding fluid through step-by-step storage, multi-stage filtration and dynamic mixing, and is suitable for manufacturing of high-precision semiconductors.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of semiconductor manufacturing, and particularly relates to a semiconductor chip chemical polishing solution supply method. BACKGROUND

[0002] Chemical mechanical polishing (CMP) is a key process for wafer surface planarization in semiconductor manufacturing, widely used in integrated circuit production. In the CMP process, the quality and supply stability of the chemical polishing solution directly affect the polishing effect and chip performance. The traditional polishing solution supply method usually pre-mixes and stores the polishing particle suspension, chemical additives and diluents, which easily leads to particle agglomeration, chemical component degradation or non-uniformity, affecting the stability and consistency of the polishing solution. In addition, the traditional method often faces problems such as flow fluctuation, inaccurate mixing ratio and difficulty in synchronous supply of multiple devices during the supply process, which is difficult to meet the requirements of high-precision semiconductor manufacturing on polishing solution purity, uniformity and stable supply. In the prior art, although some methods try to improve the quality of the polishing solution through filtration or mixing process, there is a lack of systematic optimization of component storage, precise filtration, dynamic mixing and constant flow supply, which is difficult to balance efficient preparation and stable supply. Therefore, there is an urgent need for a method that can ensure the stability of the polishing solution components, the uniformity of the particle distribution and the accuracy of the supply, in order to improve the polishing efficiency and quality of semiconductor chips. SUMMARY

[0003] The purpose of the present application is to provide a semiconductor chip chemical polishing solution supply method, which solves the problems of particle agglomeration, chemical component degradation and unstable supply caused by pre-mixing and storage in traditional polishing solution supply. By separately storing the polishing particle suspension, the chemical additive solution and the diluent, component degradation is avoided. By using a multi-stage precise filtration system to remove large-size impurities and tiny colloids, the purity and particle distribution uniformity of the polishing solution are ensured. By using a dynamic mixing device and a microfluidic mixing chip to realize accurate mixing of components according to the preset ratio, the defect of inaccurate mixing ratio is overcome. By using a dynamic fluid control system to supply the polishing solution at a constant flow rate and support multi-channel parallel supply, the problems of flow fluctuation and multi-device synchronous supply are solved. By using a corrosion-resistant storage tank and strict temperature control, the stability of the polishing solution during storage and supply is guaranteed, thereby improving the quality and supply stability of the polishing solution, and meeting the requirements of high-precision semiconductor chemical mechanical polishing (CMP) process on polishing efficiency and wafer surface quality.

[0004] To achieve the above-mentioned purpose, the present application provides a semiconductor chip chemical polishing solution supply method, which comprises:

[0005] The components of the polishing slurry are stored separately, including a polishing particle suspension, a chemical additive solution, and a diluent. The polishing particle suspension is subjected to multi-stage filtration through a precision filtration system to form a filtered suspension with a preset particle distribution. Before the supply point, a dynamic mixing device is used to precisely mix the filtered suspension, chemical additive solution, and diluent in a preset ratio to form a chemical polishing slurry. The chemical polishing slurry is supplied to the semiconductor chip polishing equipment at a constant flow rate through a dynamic fluid control system to ensure a stable supply of polishing slurry during the polishing process.

[0006] Optionally, the step of separately storing the components of the grinding slurry, including the grinding particle suspension, the chemical additive solution, and the diluent, includes: selecting silica, alumina, or cerium oxide as the grinding particles in the grinding particle suspension, with a particle size range of 10-100 nm and a suspension concentration of 20-40 wt%; preparing a chemical additive solution containing surfactants, pH adjusters, and corrosion inhibitors, with the chemical additives having a mass fraction of 10-30%; using deionized water as the diluent, and storing it in a separate sterile storage tank at a storage temperature of 15-25°C.

[0007] Optionally, the final mixing ratio of the chemical grinding slurry is: 5-25 wt% of grinding particle suspension, 2-15 wt% of chemical additive solution, and 60-90 wt% of diluent, and the pH value of the mixed grinding slurry is in the range of 2.0-5.0 or 9.0-12.0.

[0008] Optionally, the step of performing multi-stage filtration of the abrasive particle suspension through a precision filtration system to form a filtered suspension with a preset particle distribution includes: using a first-stage filtration membrane with a pore size of 0.5-2.0 μm to filter out large-sized impurity particles; using a second-stage filtration membrane with a pore size of 0.05-0.2 μm to further remove tiny particles and colloidal substances; and maintaining an ambient temperature of 20-30℃ and a filtration pressure of 0.1-0.5 MPa during the filtration process to form the filtered suspension.

[0009] Optionally, the step of precisely mixing the filter suspension, chemical additive solution, and diluent in a preset ratio using a dynamic mixing device before the supply point to form a chemical grinding slurry includes: using a multi-channel precision metering pump to deliver the filter suspension, chemical additive solution, and diluent separately, with the flow rate accuracy of the metering pump controlled within ±1%; setting a high-speed stirring module in the dynamic mixing device, with a stirring speed of 1000-3000 rpm and a mixing time of 5-30 seconds; and monitoring the particle distribution and concentration of the mixture in real time using an online light scattering detector to ensure mixing uniformity.

[0010] Optionally, the dynamic mixing device includes a microfluidic mixing chip having multiple microchannels with a channel width of 50-200 μm, for rapidly mixing the filtered suspension, chemical additive solution, and diluent.

[0011] Optionally, the step of supplying the chemical polishing slurry to the semiconductor chip polishing equipment at a constant flow rate via a dynamic fluid control system includes: controlling the flow rate of the chemical polishing slurry via a precision peristaltic pump or an electromagnetic flow valve, with a flow rate range of 50-500 mL / min; monitoring the pressure, flow rate, and pH value of the polishing slurry in real time during the supply process, with a pressure range of 0.05-0.3 MPa; and adjusting the dynamic fluid control system via a feedback control algorithm to ensure the stability of the polishing slurry supply.

[0012] Optionally, the storage tanks for the grinding particle suspension, chemical additive solution, and diluent are made of corrosion-resistant materials, and the inner walls of the storage tanks are coated with a polytetrafluoroethylene coating with a thickness of 20-50 μm.

[0013] Optionally, the temperature of the chemical polishing slurry is controlled at 20-25°C during the supply process, and the temperature stability is maintained by a circulating cooling system with a working power of 100-500W.

[0014] Optionally, the dynamic fluid control system supports multi-channel parallel supply, enabling simultaneous supply of the chemical polishing slurry to multiple semiconductor chip polishing devices, with the flow error of each channel controlled within ±2%.

[0015] This invention provides a method for supplying chemical polishing slurry for semiconductor chips. By separately storing the polishing particle suspension, chemical additive solution, and diluent, it avoids particle agglomeration and chemical degradation caused by premixed storage, ensuring the long-term stability of the components. A multi-stage precision filtration system effectively removes large-size impurities and tiny colloidal substances, forming a filtered suspension with a preset particle distribution, significantly improving the purity and uniformity of the polishing slurry. A dynamic mixing device and microfluidic mixing chip achieve precise mixing of components according to a preset ratio, and an online light scattering detector monitors the mixing uniformity in real time, overcoming the inaccurate mixing ratio defects of traditional methods. A dynamic fluid control system supplies the polishing slurry at a constant flow rate and supports multi-channel parallel supply, with flow rate error controlled within ±2%, solving the problems of flow fluctuation and simultaneous supply from multiple devices. The storage tank is made of corrosion-resistant material and coated with polytetrafluoroethylene, combined with strict temperature control (20-25℃), further ensuring the stability of the polishing slurry during preparation and supply. This invention, through systematic optimization, significantly improves the quality and supply stability of the polishing slurry, meeting the requirements of high-precision semiconductor manufacturing, and improving polishing efficiency and chip processing quality. Attached Figure Description

[0016] Figure 1 Flowchart of a method for stable supply of chemical polishing slurry for semiconductor chips provided by the present invention;

[0017] Figure 2 A flowchart of the chemical grinding fluid uniform mixing method provided by the present invention;

[0018] Figure 3 A flowchart of the constant flow rate supply method for chemical grinding fluid provided by the present invention. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature; in the description of this application, unless otherwise stated, "multiple" means two or more.

[0021] To more clearly illustrate the technical solution of the present invention, the present invention will be described in detail below with reference to specific embodiments, but it should not be construed as a limitation on the scope of protection of the present invention.

[0022] This embodiment provides an implementation method for supplying chemical polishing slurry to semiconductor chips, such as... Figure 1 As shown, based on the steps of separately storing components, multi-stage filtration, dynamic mixing, and constant flow supply, the method aims to ensure the purity, uniformity, and supply stability of the polishing slurry to meet the requirements of high-precision semiconductor manufacturing. The implementation of each step of the method is described in detail below.

[0023] Step S01: Store the components of the grinding slurry separately, including the grinding particle suspension, chemical additive solution and diluent.

[0024] Specifically, to ensure the stability of the grinding slurry components, three independent stainless steel storage tanks are used to store the grinding particle suspension, chemical additive solution, and diluent, respectively. The grinding particle suspension is stored in a tank with a polytetrafluoroethylene (PTFE) coating on the inner wall to prevent particle adsorption or chemical reactions. The chemical additive solution is stored in a similarly structured tank to maintain its chemical activity. The diluent uses high-purity deionized water and is stored in a sterile plastic tank equipped with a sealed cap to prevent contamination. Furthermore, each storage tank is equipped with a temperature control device to maintain the temperature between 15-25°C to prevent component degradation. Understandably, the storage tanks are connected to the subsequent systems via corrosion-resistant pipes to ensure that the components are not contaminated during transport.

[0025] Step S02: The abrasive particle suspension is subjected to multi-stage filtration through a precision filtration system to form a filtered suspension with a preset particle distribution.

[0026] Specifically, the abrasive particle suspension enters a precision filtration system via pipeline, which comprises a two-stage filtration device. The first stage uses a 1.0 μm pore size polypropylene filter membrane to remove large-sized impurity particles, such as agglomerates or foreign contaminants. The second stage uses a 0.1 μm pore size polyethersulfone filter membrane to further remove fine particles and colloids, ensuring a particle size distribution of 10-100 nm. Furthermore, filtration is performed at 25°C and 0.3 MPa pressure to optimize efficiency and particle distribution consistency. Understandably, the filtered suspension is monitored by an online particle detector to ensure it meets preset particle distribution requirements before being conveyed to the mixing unit.

[0027] Step S03: At the supply point, a dynamic mixing device is used to precisely mix the filtered suspension, chemical additive solution and diluent in a preset ratio to form a chemical grinding slurry.

[0028] Specifically, at the supply point near the grinding equipment, a dynamic mixing device uses a multi-channel precision metering pump to extract the filter suspension, chemical additive solution, and diluent, with flow rate accuracy controlled within ±1%. The proportions are set at 15 wt% filter suspension, 10 wt% chemical additive solution, and 75 wt% diluent. Furthermore, the device incorporates a high-speed stirring module with a stirring speed of 2000 rpm and a mixing time of 15 seconds to ensure uniform mixing of the components. Understandably, the particle distribution and concentration of the grinding slurry are monitored in real time using an online light scattering detector to verify mixing uniformity, and the resulting chemical grinding slurry is directly fed into the supply system.

[0029] Step S04: The chemical polishing slurry is supplied to the semiconductor chip polishing equipment at a constant flow rate through a dynamic fluid control system to ensure a stable supply of polishing slurry during the polishing process.

[0030] Specifically, the chemical polishing slurry is delivered to the polishing equipment via a dynamic fluid control system. A precision peristaltic pump controls the flow rate at 300 mL / min, supplemented by an electromagnetic flow valve. Furthermore, the supply process is monitored in real time by a pressure sensor (0.1 MPa), a flow meter, and a pH sensor (approximately pH 4.0). Understandably, the feedback control algorithm dynamically adjusts the pump speed and valve opening based on the monitoring data to ensure a constant flow supply, preventing fluctuations from affecting the polishing effect, and making it suitable for scenarios involving multiple devices operating in parallel.

[0031] This embodiment provides a method for supplying a chemical polishing slurry for semiconductor chips. By separately storing the polishing particle suspension, chemical additive solution, and diluent, particle agglomeration and chemical degradation caused by premixed storage are avoided, ensuring component stability. A multi-stage filtration system removes large impurities and microcolloids, forming a filtered suspension with a preset particle distribution, improving the purity and uniformity of the polishing slurry. A dynamic mixing device precisely mixes the components at a preset ratio before the supply point, forming a stable chemical polishing slurry, overcoming the problems of uneven mixing and imbalance in traditional methods. A dynamic fluid control system supplies the polishing slurry at a constant flow rate, ensuring stability during the polishing process and preventing flow fluctuations from affecting wafer surface quality. This improves the efficiency and processing accuracy of the semiconductor chemical mechanical polishing (CMP) process, meeting the requirements of high-precision semiconductor manufacturing.

[0032] In some embodiments, based on specific steps of storing the polishing slurry components separately, the aim is to ensure the quality and stability of the components to meet the requirements of high-precision semiconductor manufacturing by selecting specific polishing particles, preparing chemical additive solutions, and storing deionized water.

[0033] Specifically, silicon oxide, aluminum oxide, or cerium oxide are selected as the grinding particles in the grinding particle suspension, with a particle size range of 10-100 nm and a suspension concentration of 20-40 wt%.

[0034] Understandably, silica is chosen as the abrasive particle in the preparation of the abrasive particle suspension due to its excellent grinding performance and stability in chemical mechanical polishing (CMP). The particle size is controlled within the range of 20-50 nm and prepared using vapor deposition to ensure uniform particle size distribution. The suspension concentration is set at 30 wt%, prepared by dispersing silica particles in deionized water with the addition of a dispersant (such as sodium polyacrylate) to prevent particle agglomeration. Furthermore, the suspension is stored in a stainless steel storage tank with a polytetrafluoroethylene (PTFE) coating on the inner wall, equipped with a stirring device to maintain uniform particle distribution. Understandably, the storage tank is connected to a precision filtration system, and the delivery pipeline is made of corrosion-resistant materials to ensure the suspension remains uncontaminated before subsequent processing.

[0035] Further, a chemical additive solution containing surfactants, pH adjusters, and corrosion inhibitors is prepared, wherein the mass fraction of the chemical additives is 10-30%.

[0036] Specifically, the chemical additive solution is prepared by formulating a surfactant (such as sodium dodecyl sulfate), a pH adjuster (such as ammonia), and a corrosion inhibitor (such as benzotriazole), with the total mass fraction of the additives controlled at 20%. The preparation process is carried out in a clean room using high-purity reagents to avoid the introduction of impurities. The surfactant is used to reduce the surface tension of the polishing slurry, the pH adjuster controls the solution's acidity or alkalinity, and the corrosion inhibitor protects the metal layer on the wafer surface. Furthermore, after preparation, the solution is stored in a corrosion-resistant stainless steel storage tank, the inner wall of which is also coated with polytetrafluoroethylene (PTFE), and the storage temperature is maintained at 20°C to maintain chemical stability. Understandably, the solution is delivered to the mixing device via a precision metering pump to ensure the accuracy of subsequent mixing ratios.

[0037] Furthermore, deionized water is used as the diluent and stored in a separate sterile storage tank at a temperature of 15-25°C.

[0038] Specifically, deionized water with a resistivity greater than 18 MΩ·cm is selected as the diluent and prepared using a multi-stage reverse osmosis and ultraviolet sterilization system to ensure sterility and the absence of impurities. The deionized water is stored in an independent sterile polyethylene storage tank equipped with a sealed lid and filter vents to prevent external contaminants from entering. Furthermore, the storage tank has a built-in temperature control system to maintain the storage temperature at 20°C, and a circulating cooling device ensures temperature stability. Understandably, the storage tank is connected to a dynamic mixing device via corrosion-resistant pipes, the inner walls of which are made of polytetrafluoroethylene (PTFE) to ensure that the deionized water maintains high purity during transportation, meeting the requirements for preparing chemical grinding slurries.

[0039] In some embodiments, the final mixing ratio and pH range of the chemical polishing slurry are further specified, aiming to ensure the performance stability of the polishing slurry and meet the requirements of high-precision semiconductor chemical mechanical polishing (CMP) by precisely controlling the mixing ratio and pH.

[0040] Specifically, the final mixing ratio of the chemical grinding slurry is as follows: the grinding particle suspension accounts for 5-25 wt%, the chemical additive solution accounts for 2-15 wt%, the diluent accounts for 60-90 wt%, and the pH value of the mixed grinding slurry is in the range of 2.0-5.0 or 9.0-12.0.

[0041] Understandably, during the preparation of the chemical polishing slurry, a multi-channel precision metering pump is used to extract the polishing particle suspension, chemical additive solution, and diluent from their respective storage tanks, setting the final mixing ratio to 15 wt% polishing particle suspension, 8 wt% chemical additive solution, and 77 wt% diluent. The polishing particle suspension uses silica particles (size 20-50 nm, concentration 30 wt%), the chemical additive solution contains surfactants, pH adjusters, and corrosion inhibitors (total mass fraction 20%), and the diluent is high-purity deionized water (resistivity > 18 MΩ·cm). The mixing process is carried out in a dynamic mixing device with a built-in high-speed stirring module (stirring speed 2000 rpm, mixing time 15 seconds) to ensure uniform dispersion of components. Furthermore, to meet specific CMP process requirements, the pH value of the polishing slurry is adjusted to 10.5 by adding ammonia, falling within the alkaline range of 9.0-12.0, suitable for polishing copper or oxide layers. After mixing, the pH value is monitored in real time by an online pH sensor to ensure stability. Understandably, the mixed grinding fluid is immediately delivered to the dynamic fluid control system to maintain a constant flow rate to the grinding equipment, thus avoiding fluctuations in ratio or pH value that could affect the grinding effect.

[0042] In some embodiments, the precision filtration process of the grinding particle suspension is further clarified, aiming to form a filtered suspension with a preset particle distribution through two-stage filtration and environmental control, so as to meet the requirements of high-precision semiconductor chemical mechanical polishing (CMP) for the purity and uniformity of the polishing slurry.

[0043] Specifically, a first-stage filtration membrane with a pore size of 0.5-2.0μm is used to filter out large-sized impurity particles.

[0044] Understandably, the abrasive particle suspension (using silica particles, 20-50 nm in size, 30 wt% concentration) is transported from the storage tank to the precision filtration system via corrosion-resistant pipes. The first-stage filtration uses a 1.0 μm pore size polypropylene membrane installed in a stainless steel filter to remove large-sized impurities, such as agglomerated particles or foreign contaminants, from the suspension. Furthermore, the filtration process is conducted in a clean room, and the filter is equipped with a pre-cleaning function to avoid cross-contamination. Understandably, after the first-stage filtration, the suspension enters the second-stage filtration unit through pipes whose inner walls are coated with polytetrafluoroethylene (PTFE) to ensure no additional impurities are introduced.

[0045] Furthermore, a second-stage filtration membrane with a pore size of 0.05-0.2μm is used to further remove fine particles and colloidal substances.

[0046] Specifically, the suspension after the first-stage filtration enters the second-stage filtration device, which uses a polyethersulfone membrane with a pore size of 0.1 μm to further remove fine particles and colloidal substances, ensuring that the particle size distribution is strictly controlled within the range of 10-100 nm. Furthermore, the second-stage filter is equipped with a high-pressure pump to maintain a filtration pressure of 0.3 MPa, promoting efficient filtration while preventing membrane clogging. Understandably, the filtered suspension is analyzed in real time by an online particle size analyzer, and after verifying that it meets preset requirements, it is then transported to the dynamic mixing device.

[0047] Furthermore, during the filtration process, the ambient temperature is maintained at 20-30℃ and the filtration pressure is 0.1-0.5MPa to form the filtration suspension.

[0048] Specifically, the entire filtration process takes place in a temperature-controlled cleanroom, with the ambient temperature maintained at 25°C by an air conditioning system to prevent temperature fluctuations from affecting particle dispersion. The filtration pressure is regulated by a precision pressure pump, set at 0.3 MPa, to ensure filtration efficiency and membrane stability. Furthermore, the filtration system is equipped with temperature and pressure sensors to monitor environmental parameters in real time. If a deviation is detected, the pump speed or heating device is automatically adjusted to maintain stable conditions. Understandably, after completing two stages of filtration, the resulting filtration suspension directly enters the subsequent mixing unit, ensuring uniform particle distribution and the absence of impurities, meeting the requirements of high-precision CMP processes.

[0049] In some embodiments, such as Figure 2 As shown, the process of achieving precise mixing using a dynamic mixing device before the supply point is further clarified. This aims to ensure the uniformity and stability of the chemical polishing slurry through precise metering, rapid stirring, and real-time monitoring, thereby meeting the requirements of high-precision semiconductor chemical mechanical polishing (CMP).

[0050] Step S51: Use a multi-channel precision metering pump to deliver the filtered suspension, chemical additive solution and diluent respectively, and control the flow accuracy of the metering pump within ±1%.

[0051] Specifically, in the dynamic mixing device before the supply point, three multi-channel precision metering pumps are configured to draw the filtered suspension (silica particles, size 20-50 nm, concentration 30 wt%), the chemical additive solution (containing surfactants, pH adjusters, and corrosion inhibitors, mass fraction 20%), and the diluent (deionized water, resistivity >18 MΩ·cm) from the storage tank, respectively. The flow rate accuracy of each metering pump is controlled within ±1%, and the mixture is precisely delivered to the mixing chamber according to a preset ratio (15 wt% filtered suspension, 8 wt% chemical additive solution, and 77 wt% diluent). Furthermore, the metering pumps are driven by servo motors and equipped with flow sensors for real-time calibration to ensure stable delivery ratios. Understandably, the delivery pipelines are lined with polytetrafluoroethylene (PTFE) to prevent component contamination or adsorption.

[0052] Step S52: Set a high-speed stirring module in the dynamic mixing device, with a stirring speed of 1000-3000 rpm and a mixing time of 5-30 seconds.

[0053] Specifically, the dynamic mixing device incorporates a high-speed stirring module with a stainless steel impeller coated with polytetrafluoroethylene (PTFE) for corrosion protection. The stirring speed is set to 2000 rpm, and the mixing time is controlled within 15 seconds to ensure rapid and uniform mixing of the filtered suspension, chemical additive solution, and diluent. Furthermore, the stirring module is equipped with a frequency converter, which dynamically adjusts the rotation speed according to the component viscosity, preventing excessive shearing that could disrupt particle distribution. Understandably, the mixing chamber is designed with a conical structure to optimize fluid mixing efficiency, reduce dead zones, and ensure the uniformity of the grinding slurry.

[0054] Step S53: Monitor the particle distribution and concentration of the mixture in real time using an online light scattering detector to ensure uniform mixing.

[0055] Specifically, an online light scattering detector is connected to the outlet of the mixing unit to monitor the particle size distribution and concentration of the chemical grinding slurry in real time. The detector uses laser light scattering technology to analyze whether the particle size is maintained within the 20-50 nm range and whether the concentration meets the preset ratio (15 wt% grinding particles). Furthermore, the detector is linked to the control system; if a deviation in particle distribution or concentration is detected, it automatically feeds back to the metering pump to adjust the flow rate or extend the stirring time. Understandably, the monitoring data is presented in real time on a digital display screen. After ensuring the homogeneity of the mixture meets the CMP process requirements, it is then supplied to the dynamic fluid control system.

[0056] In some embodiments, the application of microfluidic mixing chips in dynamic mixing devices is identified, aiming to achieve rapid and uniform mixing of filter suspensions, chemical additive solutions and diluents through microchannel design, to meet the requirements of high-precision semiconductor chemical mechanical polishing (CMP) for the uniformity of polishing slurry.

[0057] Specifically, the dynamic mixing device includes a microfluidic mixing chip with multiple microchannels having a channel width of 50-200 μm, used to achieve rapid mixing of the filtered suspension, chemical additive solution, and diluent.

[0058] Understandably, the core component of the dynamic mixing device is a microfluidic mixing chip, made of silicon-based material and coated with a corrosion-resistant polytetrafluoroethylene (PTFE) coating. The chip contains multiple microchannels, each 100 μm wide, arranged in a Y- or T-shape to ensure that the filtered suspension (silicon oxide particles, 20-50 nm in size, 30 wt%), the chemical additive solution (containing surfactants, pH adjusters, and corrosion inhibitors, 20% by mass), and the diluent (deionized water, resistivity >18 MΩ·cm) enter the chip at preset ratios (15 wt%, 8 wt%, and 77 wt%). Furthermore, the microchannels are driven into the mixture by a precision metering pump (flow rate accuracy ±1%). The channel geometry promotes turbulence, achieving rapid mixing within 5-10 seconds to form a homogeneous chemical polishing slurry. Understandably, the chip outlet is connected to an online light scattering detector to monitor the particle distribution and concentration of the mixture in real time. After ensuring homogeneity, the mixture is delivered to the dynamic fluid control system to meet CMP process requirements.

[0059] In some embodiments, such as Figure 3 As shown, the process of supplying chemical polishing slurry at a constant flow rate through a dynamic fluid control system is further clarified, aiming to ensure a stable supply of polishing slurry during semiconductor chemical mechanical polishing (CMP) to meet the requirements of high-precision manufacturing. The implementation of this method is described in detail below.

[0060] Step S71: Control the flow rate of the chemical polishing slurry by means of a precision peristaltic pump or an electromagnetic flow valve, with a flow rate range of 50-500 mL / min.

[0061] Specifically, the chemical polishing slurry (prepared by mixing a filtered suspension, a chemical additive solution, and a diluent at 15 wt%, 8 wt%, and 77 wt% respectively) is delivered to the polishing equipment via a dynamic fluid control system. The system employs a precision peristaltic pump to control the flow rate, set at 300 mL / min. The pump body uses corrosion-resistant silicone tubing to ensure the polishing slurry remains uncontaminated. Furthermore, the peristaltic pump is equipped with a high-precision stepper motor, combined with an electromagnetic flow valve for auxiliary adjustment, maintaining the flow rate within ±1% of the set value. Understandably, the pump and valves are connected to the polishing equipment via clean piping, the inner walls of which are coated with polytetrafluoroethylene (PTFE) to prevent adsorption or chemical reactions by the polishing slurry.

[0062] Step S72: Monitor the pressure, flow rate and pH value of the grinding fluid in real time during the supply process, with the pressure range being 0.05-0.3 MPa.

[0063] Specifically, the supply system integrates a pressure sensor, flow meter, and pH sensor to monitor the grinding fluid status in real time. The pressure is controlled at 0.1 MPa, and data feedback from the pressure sensor ensures pipeline stability. The flow rate is monitored by the flow meter and maintained at 300 mL / min, while the pH sensor confirms that the pH value of the grinding fluid is stable at 10.5 (alkaline range). Furthermore, sensor data is displayed in real time on the control panel; if any deviation occurs, the system automatically alarms and adjusts the pump speed. Understandably, the monitoring device uses corrosion-resistant materials to ensure long-term operational reliability.

[0064] Step S73: Adjust the dynamic fluid control system through a feedback control algorithm to ensure the stability of the grinding fluid supply.

[0065] Specifically, the dynamic fluid control system incorporates a feedback control algorithm based on the PID (Proportional-Integral-Derivative) control principle. The algorithm processes pressure, flow rate, and pH sensor data in real time. If the flow rate deviates from 300 mL / min or the pressure exceeds 0.1 MPa, it automatically adjusts the peristaltic pump speed or the opening of the electromagnetic flow valve to restore the set value. Furthermore, the algorithm is implemented using a PLC (Programmable Logic Controller), with a response time of less than 1 second, ensuring a stable supply process. Understandably, this system supports parallel supply from multiple grinding devices, with a single-channel flow error controlled within ±2%, meeting the high stability requirements of the CMP process for the grinding fluid.

[0066] In some embodiments, the material and coating requirements for the storage tanks of the grinding particle suspension, chemical additive solution and diluent are further specified, aiming to ensure the stability and purity of the components stored through corrosion-resistant materials and polytetrafluoroethylene coatings, in order to meet the requirements of high-precision semiconductor chemical mechanical polishing (CMP).

[0067] Specifically, the storage tanks for the grinding particle suspension, chemical additive solution, and diluent are made of corrosion-resistant materials, and the inner walls of the storage tanks are coated with polytetrafluoroethylene with a thickness of 20-50 μm.

[0068] Understandably, the abrasive particle suspension (silica particles, size 20-50 nm, concentration 30 wt%), the chemical additive solution (containing surfactants, pH adjusters, and corrosion inhibitors, mass fraction 20%), and the diluent (deionized water, resistivity >18 MΩ·cm) are stored in three separate storage tanks. The storage tanks are made of 316L stainless steel, which is suitable for long-term storage of chemical components due to its excellent corrosion resistance. The tanks are precision welded to ensure no leakage. Furthermore, the inner walls of the tanks are coated with polytetrafluoroethylene (PTFE) using electrochemical deposition, with a coating thickness controlled at 30 μm. The coating surface is smooth and uniform, effectively preventing abrasive particle adsorption, chemical additive degradation, or diluent contamination. The coating undergoes high-temperature curing to enhance adhesion and abrasion resistance. Understandably, the storage tanks are equipped with sealed caps and filter vents to prevent external impurities from entering. When the tanks are connected to a precision filtration or mixing system, PTFE-coated pipes are used to ensure the purity and stability of the components during transport, meeting CMP process requirements.

[0069] In some embodiments, temperature control requirements for the chemical polishing slurry during the supply process are specified, with the aim of maintaining the temperature stability of the slurry through a circulating cooling system to ensure the reliability and consistency of the high-precision semiconductor chemical mechanical polishing (CMP) process.

[0070] Specifically, the temperature of the chemical polishing slurry is controlled at 20-25°C during the supply process, and the temperature stability is maintained by a circulating cooling system with a working power of 100-500W.

[0071] Understandably, the chemical polishing slurry (prepared by mixing filtered suspension, chemical additive solution, and diluent at 15wt%, 8wt%, and 77wt%, with a pH of 10.5) is supplied to the polishing equipment via a dynamic fluid control system. During the supply process, the slurry temperature is strictly controlled at 22°C through a circulating cooling system. The cooling system employs a closed-loop water-cooling device, equipped with a high-efficiency heat exchanger and a circulating pump, with a working power set at 300W to ensure rapid heat dissipation. Furthermore, the pipes and supply unit are externally wrapped with insulating material to reduce the influence of ambient temperature, and the inner walls of the pipes are coated with polytetrafluoroethylene (PTFE) to prevent temperature fluctuations caused by reactions between the polishing slurry and the pipes. Understandably, the system integrates a high-precision temperature sensor to monitor the polishing slurry temperature in real time. If it deviates from 22°C, the cooling system automatically adjusts the circulating water flow rate or cooling power with a response time of less than 2 seconds to ensure the temperature remains stable within the 20-25°C range, meeting the CMP process requirements for slurry temperature consistency and guaranteeing polishing results and wafer surface quality.

[0072] In some embodiments, the technical implementation of the dynamic fluid control system supporting multi-channel parallel supply is specified, which aims to ensure a stable supply of chemical polishing slurry to multiple semiconductor chip polishing devices through multi-channel supply and precise flow control, thereby meeting the requirements of high-precision chemical mechanical polishing (CMP) processes.

[0073] Specifically, the dynamic fluid control system supports multi-channel parallel supply, enabling simultaneous supply of the chemical polishing slurry to multiple semiconductor chip polishing devices, with the flow error of each channel controlled within ±2%.

[0074] Understandably, the chemical polishing slurry (prepared from a mixture of filtered suspension, chemical additive solution, and diluent at 15wt%, 8wt%, and 77wt%, with a pH of 10.5) is supplied to three CMP polishing units operating in parallel via a dynamic fluid control system. The system is equipped with a multi-channel distributor containing three independent channels, each equipped with a precision peristaltic pump set at a flow rate of 300 mL / min. The pump body uses corrosion-resistant silicone tubing, and the inner walls of the tubing are coated with polytetrafluoroethylene (PTFE). Furthermore, each channel integrates an electromagnetic flow valve and a flow sensor to monitor and calibrate the flow rate in real time, ensuring that the flow error for each channel is controlled within ±2% (i.e., 294-306 mL / min). The feedback control algorithm is based on the PID principle, processing sensor data through a PLC to dynamically adjust the pump speed and valve opening, with a response time of less than 1 second. Understandably, the system supports synchronous supply, equipped with a pressure sensor (0.1 MPa) and a pH sensor (pH 10.5) to monitor the state of the polishing slurry in each channel, ensuring consistency. The distributor is modularly designed and can be expanded to more channels to meet the needs of large-scale production, ensuring the stability of the CMP process and the quality of wafer processing.

[0075] The above description is merely an exemplary embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural transformations made using the contents of the present invention specification and drawings under the technical concept of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A method for supplying a chemical polishing slurry to a semiconductor chip, characterized in that, The semiconductor chip chemical polishing slurry supply method includes the following steps: The components of the grinding fluid are stored separately, including the grinding particle suspension, chemical additive solution, and diluent; The grinding particle suspension is subjected to multi-stage filtration through a precision filtration system to form a filtered suspension with a preset particle distribution. A dynamic mixing device is used at the supply point to precisely mix the filtered suspension, chemical additive solution and diluent in a preset ratio to form a chemical grinding slurry. The chemical polishing slurry is supplied to the semiconductor chip polishing equipment at a constant flow rate through a dynamic fluid control system, ensuring a stable supply of polishing slurry during the polishing process.

2. The method for supplying a semiconductor chip chemical polishing slurry as described in claim 1, characterized in that, The step of separately storing the components of the grinding fluid, including the grinding particle suspension, the chemical additive solution, and the diluent, includes: Silica, aluminum oxide or cerium oxide are selected as the grinding particles in the grinding particle suspension, with a particle size range of 10-100 nm and a suspension concentration of 20-40 wt%. Prepare a chemical additive solution containing surfactants, pH adjusters and corrosion inhibitors, wherein the mass fraction of the chemical additives is 10-30%; Deionized water is used as the diluent and stored in a separate sterile storage tank at a temperature of 15-25°C.

3. The method for supplying a semiconductor chip chemical polishing slurry as described in claim 2, characterized in that, The final mixing ratio of the chemical grinding slurry is as follows: 5-25 wt% grinding particle suspension, 2-15 wt% chemical additive solution, and 60-90 wt% diluent, and the pH range of the mixed grinding slurry is 2.0-5.0 or 9.0-12.

0.

4. The method for supplying a semiconductor chip chemical polishing slurry as described in claim 1, characterized in that, The step of performing multi-stage filtration of the abrasive particle suspension through a precision filtration system to form a filtered suspension with a preset particle distribution includes: The first-stage filtration membrane has a pore size of 0.5-2.0μm, which filters out large-sized impurity particles; A second-stage filtration membrane with a pore size of 0.05-0.2μm is used to further remove fine particles and colloidal substances; During the filtration process, the ambient temperature is maintained at 20-30℃ and the filtration pressure is 0.1-0.5MPa to form the filtration suspension.

5. The method for supplying a semiconductor chip chemical polishing slurry as described in claim 1, characterized in that, The step of precisely mixing the filtered suspension, chemical additive solution, and diluent at a preset ratio using a dynamic mixing device before the supply point to form a chemical grinding slurry includes: A multi-channel precision metering pump is used to deliver the filtered suspension, chemical additive solution and diluent respectively, and the flow accuracy of the metering pump is controlled within ±1%. A high-speed stirring module is set in the dynamic mixing device, with a stirring speed of 1000-3000 rpm and a mixing time of 5-30 seconds; The particle distribution and concentration of the mixture are monitored in real time by an online light scattering detector to ensure uniform mixing.

6. The method for supplying a semiconductor chip chemical polishing slurry as described in claim 5, characterized in that, The dynamic mixing device includes a microfluidic mixing chip with multiple microchannels, each with a width of 50-200 μm, for rapidly mixing the filtered suspension, chemical additive solution, and diluent.

7. The method for supplying a semiconductor chip chemical polishing slurry as described in claim 1, characterized in that, The step of supplying the chemical polishing slurry to the semiconductor chip polishing equipment at a constant flow rate through a dynamic fluid control system includes: The flow rate of the chemical polishing slurry is controlled by a precision peristaltic pump or an electromagnetic flow valve, with a flow rate range of 50-500 mL / min; The pressure, flow rate, and pH value of the grinding fluid are monitored in real time during the supply process, with a pressure range of 0.05-0.3 MPa; The dynamic fluid control system is adjusted by a feedback control algorithm to ensure the stability of the grinding fluid supply.

8. A method for supplying a semiconductor chip chemical polishing slurry as described in any one of claims 1-7, characterized in that, The storage tanks for the grinding particle suspension, chemical additive solution, and diluent are made of corrosion-resistant materials, and the inner walls of the storage tanks are coated with polytetrafluoroethylene with a thickness of 20-50 μm.

9. A method for supplying a semiconductor chip chemical polishing slurry as described in any one of claims 1-7, characterized in that, The temperature of the chemical polishing slurry is controlled at 20-25℃ during the supply process, and the temperature stability is maintained by a circulating cooling system with a working power of 100-500W.

10. A method for supplying a semiconductor chip chemical polishing slurry as described in any one of claims 1-7, characterized in that, The dynamic fluid control system supports multi-channel parallel supply, enabling simultaneous supply of the chemical polishing slurry to multiple semiconductor chip polishing devices, with the flow error of each channel controlled within ±2%.

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